also, my properties perform pretty well (both in terms of cashflow and appreciation), which makes managing them much more enjoyable (the job would be pretty miserable if you're not making much money, or losing money).I would assume you're correct -- that people who have C and lower properties (or properties that don't make much money) often drop out pretty quickly...managing a D property would be extremely stressful and difficult--not a job I'd want (not for any amount of cashflow)!

Second, the market is going down so what happens if you are 80% borrowed against your primary and then the value drops 20%?

Each time you make a major status change or price drop, it should pop to the top of everyone's MLS results and folks will take a second look.

You're talking about an 70% drop there in your example...that's not normal at all.

Temperature control.  

@Jerad GraceI typically drop off cookies or popcorn tins with a card.

Try to get the market rent but don't sweat it if you have to drop it $25-$75/mo to get it rented faster.

I don't know what the story is here but rent should not have dropped that much. 

The reality is that mortgage rates aren’t dropping back to 3’s and 4’s again for a long time, if ever with all this government spending.

How could you be underwater if you only dropped $100k on renovations, which seems reasonable for a two-family fixer upper?